1. Technical Field
The present disclosure relates to an image forming apparatus.
2. Related Art
Some of existing image forming apparatuses are configured to avoid erroneously deciding that the recording medium identifier has failed, by restricting, when the built-in CPU decides that the recording medium or the paper feed cassette is absent on the basis of a detection result from the paper sensor, the recording medium identifier from performing a self-diagnosis function for identifying the type of the recording medium according to the level of gloss. In addition, in some image forming apparatuses the paper feed cassette includes a plurality of projecting portions and the main body of the apparatus includes a plurality of switches to be pressed by the respective projecting portions, so that the image forming apparatus can decide whether the paper feed cassette is mounted by detecting a pressed state of the switches, and identify the type of the recording medium placed in the paper feed cassette according to the position of the switch that has been pressed. In the image forming apparatus thus configured, the signal line on one of the sides of the switches is used in common and connected to the ground of the apparatus main body, and the switches do not output a detection signal until the paper feed cassette is mounted in the apparatus main body so that the frame ground of the apparatus main body and the frame ground of the paper feed cassette are brought into contact with each other. Such a configuration prevents erroneous detection of the type of the recording medium originating from irregularity of the timing that each of the switches is pressed.
In the mentioned image forming apparatus, the sensor for detecting whether the paper feed cassette is mounted is located inside a cassette chamber provided in the apparatus main body for mounting the paper feed cassette, so as to detect whether the paper feed cassette is mounted according to whether the paper feed cassette is in contact with the sensor.